Alloy



Patented Dec. 1, 1942 UNITED STATES PATENT OFFICE ALLOY Cecil Spencer Sivil, Roselle, N. 1.. assignor to Baker & Company, Inc

ration of New Jersey Application December 20, 1941, Serial No. 423,793

No Drawing.

., Newark, N. 3., a corpo-.

3 Claims. (Cl. 75-172) alloys of great electflcalresistance. It is a further object of my invention to provide suchalloys of low specific gravity and low cost.

This applicationis a continuation in part of my application Serial-No. 401,653 filed July 9, 1941, which in turnis a continuation in part of my application Serial No. 378,376, ,flled February 11, 1941.

The alloys according to my invention comprise palladium, ruthenium, and iridium. In such alloys the palladium content may be as low as about 60% and as high as about 95%, the ruthenium content being as low as 0.5% and as high as about 20%, whereas the iridium content comprises at least 2.5% of the whole alloy. I prefer alloys wherein the ruthenium content lies between about 1%? and a maximum of about In its best embodiments the alloys consist entirely of palladium, ruthenium, and iridium in the proportions specified herein, although, of course, minor quantities of other metals may be present so long as they do not substantially afl'ect the beneficial properties and characteris tics of my alloys.

Particularly advantageous are alloys within the limits of 80% to as;% palladium, 1% to 10% ruthenium, and 2.5% to 10% iridium, such as alloys of 80% palladium 10% ruthenium and 10% iridium, or of 90% palladium 5% ruthenium and 5% iridium. Likewise, alloys comprising palladium, ruthenium and iridium, according to my invention, may also contain advantageously a substantial content of rhodium, such as from 2.5% to 37% rhodium, in which case the maximum palladium content will be 94.5% and the maximum-iridium content will be 37%, such as alloys of 80% palladium 5% ruthenium 5% iridium and 10% rhodium, or 01 90% palladium 2.5% ruthenium 2.5% iridium and 5% rhodium. In order to illustrate the properties of the alloys according to this invention, I may state that an alloy of 80% palladium 5% ruthenium 10% rhodium and 5% iridium has a tensile strength of 133,900 lbs. per square inch when hard, and of 94,200 lbs. per square inchwhen annealed, and an elongation of 27% on 2-inches when annealed. trical resistivity of 200 ohms/mil ft.

What I claim is:

1. An alloy of palladium, ruthenium and iridium comprising to about 95% palladium, 0.5% to 20% ruthenium, and 2.5% to 39.5% iridium.

2. An alloy of palladium, ruthenium and iridium comprising to 96.5% palladium, 1% to 10% ruthenium, and 2.5% to 10% iridium.

3. An alloy of palladium, ruthenium and iridium comprising about palladium, about 5% ruthenium, and about 5% iridium.

CECIL S. SIVIL.

The alloy, likewise, possesses an elec- 

